This paper presents a new scheme for power system stability enhancement using emergency control. The proposed scheme is based on a grid rulc-based fuzzy classification approach for power system security evaluation. Generator tripping is adoptcd as the emergency control technique followed by the necessary load shedding, if needed. The proposed strategy was tested through numerical simulation for a typical study system. Good results in enhancing system security and limiting system deterioration were obtained. The presented technique also exhibits simple design and fast operation since it requires only one local measurement per generator. On-line implementation is also discussed.